The present invention relates in general to cooking appliances. In particular, the present invention relates to an interface for cooking appliances.
Heaters in cooling appliances, such as glass-ceramic cooktops, often have the radiant heater located underneath a piece of ceramic-glass or constructed such that the heating element is in direct contact with the cookware as in a conductive system. The heater or heaters are generally controlled with a known form of electromechanical regulator or some type of electronic control that cycles the heater on and off using an adjustable time base technology. This technology mechanically accomplishes the two step on, one step off function, but will not communicate with electronic controllers. Another type of control alters the electrical supply wave form to change the power applied to the heaters.
One such control is an infrared touch control that uses reflected infrared light as the user interface. Another known user interface for an electronic control in glass-ceramic cooktops is the field effect sensor technology. This technology uses electrostatic fields that emanates around a touch pad. When the user interrupts this field the controller interprets this as human actuation. The capacitance touch sensor is another known input to an electronic control for this application. One other input device that the user may interface with an electronic control is the membrane switch.
All of the above systems have their problems and limitation. The electromechanical regulators are time based controls that turn on the heaters with full power for a period of time and then off for a period of time. The shortest cycle time they can manage is anywhere from one to two minutes. This type of control gives very poor heat regulation, especially at the lower heat settings. The infrared touch control has problems of insensitive, incorrect or random switch actuation that can occur due to a spill on the cooktop surface or placing a pan or other items over or against the touch pad. The field-effect and capacitance touch sensors have problems with incorrect or random switch actuation due to RF and e-field interference. Moisture presents extreme difficulties for conventional capacitance sensors. Plastic membrane switches are very heat sensitive and present a problem due to varying texture and tactile feel. They often appear wrinkled or wavy, become dull with use and are difficult to color match with adjacent panels and substrates. The membrane edges also trap dirt, which can contaminate the signal and create cleaning problems. Presently, electronic controllers accomplish the safety agencies"" two step on, one step off function by adding redundant circuitry.
One embodiment of the present invention provides a cooking controller assembly, including a heating element, a push-to-turn rotary switch, and an electric controller. The heating element is coupled to the push-to-turn rotary switch and the electric controller. The push-to-turn rotary switch is manually pushed and turned to selectively connect power to the heating element. The electric controller is coupled to the push-to-turn rotary switch and the heating element, and electrically controls the power to the heating element in relation to the manual rotation of the push-to-turn rotary switch.